We can borrow some ideas from the nature of the light flavor scalar mesons, which provide a subject of an intense and continual controversy in establishing the meson spectrum, the most elusive things are the quark configurations of
the \(f_0(980)\)  and \(a_0(980)\) , which have almost the degenerate masses. In the scenario of the hadronic dressing mechanism, the scalar mesons \(f_0(980)\)  and \(a_0(980)\)  have small or large \(q\bar{q}\)  cores of the typical \(q\bar{q}\)  meson size, or large \([qq]_{\bar{3}}[\bar{q}\bar{q}]_3\)  cores in the relative S-wave with some \(q\bar{q}\)  components in the relative P-wave,
the bare \(q\bar{q}\)  or \([qq]_{\bar{3}}[\bar{q}\bar{q}]_3\)  cores are dressed by the hadronic interactions with the pseudoscalar mesons,
the strong couplings to the hadronic
channels or nearby thresholds enrich the pure \(q\bar{q}\)  or \([qq]_{\bar{3}}[\bar{q}\bar{q}]_3\)  states with other components and spend part or most part of their lifetime as the virtual
\(K^+K^-\)  or \(\bar{K}^0K^0\)  states [1]}, [2]}, [3]}, [4]}, [5]}, [6]}. The QCD sum rules indicate that
the nonet scalar mesons below \(1\,\rm { GeV}\)  are the two-quark-tetraquark mixing states with large or small two-quark components [7]}, [8]}. Without introducing mixing effects in one way or the other, it is difficult to reproduce the experimental values of the masses of the nonet scalar mesons below \(1\,\rm { GeV}\)  [9]}, [10]}, and account for the decays.
In summary, the QCD sum rules favor the hadronic dressing mechanism [5]}, [6]}, [7]}, [8]}.
